Small shrub, 0.3–2.5 m; young shoots scaly Leaves 1.8–8 × 0.5–2 cm, narrowly oblong or oblong-elliptic, apex acute to rounded, upper surface with scales, especially on midrib and at base, lower surface densely covered with brown to dark brown peltate scales. Flowers 1(–2), in an inflorescence borne in the axils of the upper leaves; calyx lobes 2–3 mm, sometimes ciliate; corolla white to deep pink or mauve, funnel-shaped, 15–37 mm, outer surface of tube sparsely scaly and pubescent; stamens 10; ovary densely scaly, impressed below the declinate style that is scaly and/or pilose towards base. Flowering April-May. Royal Horticultural Society (1997)
Distribution Bhutan China S Tibet, Yunnan India Sikkim, Arunachal Pradesh
Habitat 2,000–4,000 m
RHS Hardiness Rating H4
Conservation status Least concern (LC)
An evergreen shrub up to 8 ft high in the wild, with slender branches covered when young with brown scales. Leaves 1 to 3 in. long, 3⁄8 to almost 1 in. wide, narrow-elliptic or oblong-lanceolate, tapered or somewhat abruptly narrowed at both ends, dark green, glabrous and sometimes scaly above, underside paler green, sometimes slightly glaucous, sprinkled with shining brown scales; leafstalk 1⁄8 to 3⁄4 in. long. Flowers produced in April singly or in pairs from the uppermost leaf-axils on the previous season’s growths, bud-scales persisting during flowering and concealing the pedicels, which are up to 3⁄8 in. long. Calyx shortly five-lobed, usually scaly. Corolla funnel-shaped, 3⁄4 to 11⁄2 in. long, with five rounded, spreading lobes, varying in colour from white to various shades of purple or rose, scaly and usually more or less downy on the outside. Stamens ten, downy. Ovary scaly; style downy in the lower half or glabrous, sometimes scaly. Bot. Mag., tt. 5060, 8802. (s. Virgatum)
R. virgatum is a species of wide range, from E. Nepal, through Sikkim (where J. D. Hooker discovered it in 1849) as far east as Yunnan, where Delavay collected the type of R. oleifolium around 1884. It was introduced by Hooker in 1850 and reintroduced by Forrest (as R. oleifolium) in 1906. There have been several sendings since then, the most recent being by the University of North Wales expedition to E. Nepal (B. L. & M. 298).
Although it has been found as high as 12,500 ft, R. virgatum is not a very hardy species and is mainly confined in the wild to elevations of 7,000 to 10,000 ft, and prefers open, dry sunny places or thin pine woodland. It is uncommon in cultivation.
R. virgatum is the only member of the series to which it gives its name. Of the two species once grouped with it, R. oleifolium is now considered to be synonymous and R. racemosum has been transferred to the Scabrifolium series. From that series R. virgatum differs in having the flowers solitary in each leaf-axil, or at the most in pairs. The glabrous leaves distinguish it from all members of that series except R. racemosum and R. hemitrichotum, and they have the leaves glaucous beneath; in R. virgatum the leaves are green beneath.
The synonym R. oleifolium (page 798) should be deleted.
subsp. oleifolium (Franch.) Cullen R. oleifolium Franch. – Flowers smaller (corolla to 1 in. long against 1 to 11⁄2 in. in the typical subspecies), white or pink (against pale to deep pink or mauve). It has on the whole a more easterly distribution than the typical subspecies, not occurring further west than south-east Tibet.
R. oleifolium Franch.
Corolla 15–25mm, tube 8–15mm, white or pink.
Distribution China (SE Tibet, W & N Yunnan).
Taxonomic note (R. oleifolium Franch.)
This is a distinctive species on account of the axillary inflorescences.
Corolla 25–37mm, tube 11–20mm, pale or deep pink to mauve.
Distribution Nepal, India (Sikkim, Arunachal Pradesh), Bhutan, China (S & SE Tibet).
Awards AM 1973 (Maj. A.E. Hardy, Sandling Park, Kent); flowers white.